Programming



Sept; 6, 1966 R. E. GlLcHRls-r ETAL 3,270,812

PROGRAMMING Filed Fb. 16. 1962 3 Sheets-Sheet 1 INVENTORS RE. GlLCHRIST RH. LANGENHEIM A TTORNE V5" R. E, GlLcHRls'r ETAL 3,270,812

Sept. 6, 1966 PROGRAMMING 5 Sheets-Sheet 2 Filed Feb.- 16. 1962 v W E. www MDE M m R mmA fw GL N H RR Sept 5, 1936 R. E. GlLcHRlsT r-:TAL 3,270,812

PROGRAMMI NG 5 Sheets-Sheet 3 Filed Feb. 16. 1962 lrates This invention relates to method and apparatus for programming. .ln one aspect the invention relates to a pulse-actuated programmer. In another aspect the invention relates to iluid tlow programming means cornprising means for programming flow-producing or tlowcontrolling means. Inanother aspect the invention relates to means for establishing a varying transition zone in miscible flooding. In another aspect the invention relates to a method for programming, utilizing constant interval electrical pulses. ln another aspect the invention relates to a method for programming flow of tluid by programming uid how-producing or flow-controlling means. In another aspect the invention relates to a method for miscible displacement comprising the establishment of a transition zone by gradually varying from all of a first iluid to all of a second uid in discrete steps by programming flow ofthe tluids.

One method for the recovery of oil from underground reservoirs is by miscible fluid displacement. This comprises the injection of a solvent for the fluid to be produced, followed by a drive, for example with natural gas, to displace the solvent. Frequently a slug of the solvent, such as liquefied petroleum gas, is forced through the reservoir by the following natural gas. The eiliciency of the displacement can be improved, through reduc- .ing the severity of fingering, by establishing a transition zone between the reservoir Huid and the displacing medium'by injecting into the formation alternate slugs of the higher viscosity and the lower viscosity materials, thus'forming within the formation a transition zone of gradually varying viscosity between the higher and the lower viscosity materials. Such a zone can be created by manually switching the injection flow' from one to the other Vfluids in varying proportions. However, it is desirable to form the transition zone autr matically without close manual supervision. We have round that such a zone can be formed automatically by suitable programming of the fluid injection.

An object of this invention is to provide a method for programming.

Another object of this invention is to provide programming apparatus.

Another object of this invention is to provide method and apparatus for automatically forming a transition zone in miscible fluid flooding.

Other aspects, objects and the advantages of our invention are apparent in the written description, the draw' ing and the claims.

According to our invention, programming is accomplished by generating a plurality of electrical pulses, counting the pulses and alternating a circuit connection once for a first predetermined number of pulses and once for a second predetermined number of pulses. Our programming method is applicable to the control of flow of y different lluids by utilizing switching means to switch from one to another of iluid pumps or by switching valves connecting with more than one source of different fluids. Ourmethod of controlling the variation of uid flow is useful in the preparation of a transition zone between lluids'of dierent viscosity in miscible ooding operations by gradually changing from all of one fluid to all of another fluid in discrete steps.

Also according to our invention there is provided a programmer comprising an electrical pulse generator, and

3,270,812 Patented Sept. 6, 1966 at least two counters actuated by the pulses from the generator, and which in turn complete an electrical circuit at periods equal for each counter but unequal for the two counters. Our programmer is especially useful in the control of fluid tlow by turning on and off a source of power to uid pumps or by controlling valves con- -necting with more than one source of different iluids.l The apparatus for'control of lluid llow can be used in the preparation of a transition zone between fluids of different viscosities in miscible fluid flooding operations.

In the drawing, FIGURE 1 is a diametric view of a programmer apparatus housingaillustrating the control and indicator panel.

FIGURE 2 is a schematic circuit diagram of our programmer.

FIGURE 3 is a schematic circuit diagram illustrating the functional relationship between major components of our programmer, and showing the use of a cut-off counter.

FIGURE 4 is a schematic representation of a pair of flow-control means controlled by our programmer.

FIGURE 5 is a schematic elevation, partly in cross section, of our invention embodied in an underground uid llooding operation. l

In the programmer illustrated in FIGURE 1 a pair of counter dials 1l and 12 are provided and adjustment of the counters is made by knobs 13 and 14, respectively. Counter dials 11 and 12 are calibrated on an outer scale, indicated by pointers 16 and 17, in multiples of 20, up to 400, and, on inner Vernier scales, indicated bypoints 18 and 19, in single units up to 20. Each counter therefore can be set for a specific number of pulses between 1 and 400. These counters are of the type which complete a circuit when a lpulse is received c'orresponding with the number of pulses for which the instrument is set and which, at the next succeeding pulse, start the cycle again. For example, if one of the coufnters is set for l0 pulses, each tenth pulse completes' a contact in the counter. These counters are represented schematically in FIGURE 2 by the dashed rectangles bearing the reference numerals 41 and 42. An impulse generator is provided and its indicator dial .is represented by dial 21. This dial is calibrated in pulse intervals ranging between l second and 28 days. The timer is represented schematically in FIGURE 2 by the reference numeral 43. This timer is controlled by a knob 22 which adjusts the impulse interval and at the same time indicates the interval selected on dial 21. Two-pole single throw switches are indicated at 23, 24 and 26. Switch 23 is the power switch for the programmer. Switch 24 is the on-off switch for timer 43. Switch 26 is connected in parallel circuits and determines whether the pulse interval is equal to the interval selected on timer 43 or is halved, the circuit being explained with respect to FIG- URE 2. Switch 27 is a two-pole, double throw switch adapted for momentary operation in the down position and being stable in the central or off position and in the up position. This switch is used to control the programmer for a single cycle of operation or to permit it to proceed through a number of cycles. Switches 28 and 29 are single-pole, double-throw switches, switch 28 being a. selector switch for manual or automatic operation and switch 29 determining which of the control circuits is actuated in the manual position. This switch can also be used to determine which circuit is actuated at the beginning of the automatic sequence. Electrical outlets 31 and 32 are provided for the controlled circuits to be programmed. Push button switches 25 and 30 also are on the face of the housing, switch 25 for manually producing single pulses, to change the outlet energized when on automatic control, for example, and switch 30 to permit relay 37 to return to home position.

As illustrated in FIGURE 2, the complete programmer comprises switches 23, 24, 25, 26, 27, 28, 29 and 30, electrical outlets 3l and 32, plug 33, fuse 34, relays 3d and 37, rectifier 38, counters 4-1 and 42, timer 43, switches 44, 4S. 46 and 47. and indicator lights 48, 49, 50 and 5l.

The letters and numbers in the circles associated with counters 41 and 42 are the designations applied to the terminals of a commercial counter, Type HZ 4OA6, contacts .fe-242, similar to that illustrated in Bulletin 720 of the Eagle Signal Company, Moline, Illinois. Each of these counters includes a clutch coil connected between terminals L1 and A, a count coil connected between terminals Ll-M, normally open contacts connected between terminals B-L2 and 244, and normally closed contacts connected between terminals -3-1. When the clutch coil is energized the three switches are actuated, that is, the switches between B-L2 and 2-4 are closed and the switch between terminals 3 1 open. This situation remains as long as the clutch coil is energized, until the count coil receives the number of pulses for which the counter is adjusted on the dial, at which time a mechanical release of the contacts, permitting the switches to return to their normal position, is effected.

Timer 43 can be a Type MG-lOOO timer made by Gorrell and Gorrell, Westwood, New Jersey. This timer includes a driving motor and a plurality of cam mechanisms which actuate the connected switches at different rates. The cam wheel illustrated is representative of the various cam mechanisms which can be selected by moving the knob 22. Provision is made on this counter for the installation of the switches 44-47. In this particular installation the switches are located for actuation at 90 degree intervals. The switches are normally closed but are held in the open position by the cam wheel until the depression inthe cam is reached, at which time the switch returns momentarily to its normally closed position.

Rectifier 38 isa catalog PA-97 rectifier made by Automatic Electric, Northlake, Illinois. Relay 37 in the particular embodiment illustrated in FIGURE 2 is a rotary stepping switch, a series OCS relay, and AE rotary stepping switch, also made by Automatic Electric. This relay steps once for each pulse received from the counter circuits. At each step one of the outlets 31 and 32 is connected to the relay contacts illustrated. This is a schematic representation, being actually the contacts arranged alternately around the stepping switch. Although not normallyneeded in the operation of the circuit of FIGURE 2, a push button homing switch 30 provides means whereby the stepping switch can be made to return to its home position, internal interruptor contacts being provided to send the necessary pulses. Switch 30 is not required -in normal operation when the rotary stepping switch of relay 37 is adapted for continuous operation through more than one revolution and the controlled circuit outlets 3l and 32 are energized alternately. However, when the stepping switch must be returned for each cycle of operation, or when an irregular pattern for energizing the outlets is provided, such a homing switch is necessary. The operation of a homing circuit is lwell known-and is not described here in detail.

In the operation of the programmer illustrated in FIG- URE 2, timer 43 is set for a desired pulse interval, counter 41 is set for a first predetermined number of pulses and counter 42 is set for a second predetermined number of pulses. For example, counter 42 is set for ten pulses and counter 41 for nine pulses. Switch 23 is closed to supply power to the unit, and switch 24 closed to start timer 43. Switch 26 is actuated to the desired position which determines the frequency of pulses transmitted to the counters. With the contacts of switch 26 open, switches 44 and 45 are effective in transmitting pulses to the desired parts of the circuit, while switches 46 and 47 are inoperative due to the open circuit. On the other hand, when the contacts are closed all of the switches are operative. Thus, with the contacts of switch 26 closed the number of pulses is two times the number transmitted with the contacts open.

When the apparatus is turned on, the contacts of relay 37 are in position to connect either outlet 31 or outlet 32, and the corresponding pilot light 50 or 51 lights. If it is desired to start the operation on the opposite outlet, either the switch 28 is moved to manual position and the switch 29 moved to the desired outlet, or, if automatic operation is contemplated, the usual case, switch 25 is actuated to transmit one pulse to relay 37, thus switching its contacts to the opposite outlet. Switch 25 provides the pulse by completing the alternating current supply to rectier 38, thus causing a pulse in the D.C. output through relay 37. If the circuit to rectifier 38 is already closed, switch 25 interrupts the circuit momentarily, but this latter situation normally would not occur in the usual operation of the apparatus. Actuating switch 27 to the momentary closed position, the position marked 1, energizes relay 36 which closes its contacts permitting the application of power to terminals L2, and A of both counters. Supplying power to terminals A energizes the clutch coils, thus moving the switches to the opposite position from that illustrated in the drawing. The closing of the contacts between terminals B-L2 and 2-4 permits power to be supplied continuously to terminals A until both counters count out at the same time. That is, as long as either of the counters has its contacts latched in there is a circuit connection between terminal 4 and terminal 2. The terminals 2 are connected together and each is connected to the corresponding terminal L2. For the counter which has not reached its predetermined number of counts, the contacts between B and L2 also are closed, thus keeping the clutch coil energized.

When either counter has received the predetermined number of pulses through its count coil the contacts between B-LZ, 3-1 and 4-2 are released to return to their normal position. This causes a circuit to be completed from terminal 1 to terminal 3, thus completing the circuit `from the terminals 3 and 4 of rectifier 38 through relay 37 to aetuate this relay to cause it to step one position.

The programmer continues to run and, when either of the switches 45 and 47 is again actuated, relay M is pulsed and the counter is restarted, provided the contacts 4-2 of the other counter are not open because of simultaneous count out of the other counter. When both counters do count out at the same time, power is removed from both counters and the stepping of the rotary relay 37 discontinues because no further pulses are transmitted by the counters.

lf switch 27 is placed in the continuous position, marked infinity on the face of, the housing, the same sequence is followed except that timing out of both counters at the same time does not discontinue the operation since power is maintained to contacts L2 through switch 27. The programmer continues to operate, repeating the program each time it is completed.

In the operation described, with the counters set at 9 and l0, respectively, the sequence of operation is 9-1, 8-2, 7-3, 6-4, 5-5,;4-6, 3-7, 2-8 and 1 9. Other sequences can be obtained. For example, if the counters are set at 10 and 8, the program sequence is 8 2, 6-4, 4-6 and 2-8. The programmer also can be built with additional counters to provide more complicated programs and more than two outlets can be provided to permit programming more than two conditions.

FIGURE 3 is a schematic block diagram of a programmer according to our invention utilizing a cut-off counter in addition to the programming counters. This apparatus comprises timer 51, first and second programming counters 52 and 53, cut-oli counter S4, relay 56 and relay 57. Because of the circuits employed, a cut-olf counter is not needed in the programmer of FIGURE 2.

In the operation of a programmer illustrated in FIG- URE 3, the sequence is similar to the operation of the programmer of FIGURE 2, except that a cut-off counter is utilized. Timer 51 is set for the desired pulse interval,

counter 52 is set for a first predetermined number of pulses and counter 53 is set for a second predetermined number of pulses. For example, counter 52 is set for ten pulses and counter 53 is set for nine pulses. Counter 54 is set for the total number of pulses for which it is desired to permit the apparatus to run. One preferred method of operation is to set counter 54 for the total number of pulses required' for one complete program cycle. In the present example, the total cycle is taken as 90 pulses. The power supply is then connected to the apparatus and timer 51 begins to run andsend pulses to the counters 52, 53 and 54 through conductor 58. Pulses at the same rate alsoare transmitted through conductor 59 which actuates relay 56 to send energizing pulses through conductor 61 and 62 to counters 52 and 53. Only one such pulse is needed to start the operation of the counter but they are transmitted continuously so that each counter begins operation on the next pulseafter counting out. Each time counter 52 or counter 53 reaches its predetermined number of pulses, a circuit is completed through conductor 63 to send a signal to relay S7. Relay 57 is one which changes connections back and forth between a pair of outlets each time a signal is received. That is, for example, if relay 57 has completed -a circuit to outlet 64 the first time a signal is received, on the next signal outlet 64 is disconnected and outlet 66 is conneeted Similarly, the next time a signal is received outietv66 is disconnected and outlet 64 is connected. In the particular apparatus and with the particular settings described, at the ninth pulse counter 53 transmits a signal to the relay 57, thus switching from outlet 64 to outlet 66. At the tenth pulse relay counter 52 transmits a signai vto relay 57 to change the connection back to outlet 64. At the eighteenth pulse (2X9) counter 53 transmits a signal which switches to outlet 66. At the twentieth pulse (2X l0) counter 52 transmits a signal which changes back to outlet 64. This operation continues until the entire cycle of 90 impulses has been completed, at which time it wiil be seen that outlet 64 was connected as follows 9.of the first impulses, 8 of the next 10 impulses, 7 of the next li) impulses, and so on down to l of 10 irnpulses, while o utlet 66 was connected through the same series of nine groups of ten pulses each, l, 2, 3, 4, 5, 6, 7, 8, and 9 pulses.- With this apparatus connected with two pumps, one powered through circuit 64 and the other other through circuit 66, the pumps can be programmed to transmit fluids in the same ratios. Similarly, outlets 64 and 66 can be used to control iiow valves. When timer 54 counts out, the entire operation stops.

In FIGURE 4 a first ow control .means 67 is actuated by electrical means 68 controlled by outlet 31 and a second fiow control means 69 is actuated by electrical means 7i conlrollcd by outlet 32. ln one embodiment means 67 and 69 are pumps and means 68 and 71 are electrical motors. while in another embodiment means 67 and 69 are valves.

ln FIGURE 5 a first valve 72 is actuatedk by electrical means 73, for example a solenoid, controlled by outlet 3i, and vulve 74 is actuated by electrical means 76 from outlet 32. FIGURE 5 also illustrates our invention applied to miscible fiuld displacement of underground petroleum oil. Oil reservoir 77 is penetrated by an injectjon well 78 and a production Well 80. Wells 78 and 80 are provided with casings 82 and 84, and with tubing strings 86 and 88, respectively. The annulus in well 78 is packed with sand or gravel 90 and a packer 92 is set around tubing 86 and the lower end of the casing. The packing of sand or gravel 90 in the well under tubing Vstring 86 insures mixing of the injected fluids within the reservoir in the space surrounding well 78. The section of tubing 88 below packer 92 can be perforated to provide better distribution of fiuids in the gravel. Also, casing 82 can be extended to the bottom of the hole, being perforated below packer 92 before packing the hole.

Lines 94, 96 and 98 connect with tubing 86 and with suitable pumps to provide for injection of LPG, oil and natural gas, respectively.

An illustration of the laminar nature of the transition zone is shown between the depleted reservoir and the oilrich reservoir intermediate injection well 78 andproduction well 80. This illustration assumes tha-t the injected constituents of the transitionA zone remain in their respective positions Without mixing, to better demonstrate the size and order of the portions injected. Actually, the portions of oil and LPG first injected through well '78 begin to mix as they are forced deeper into the formation by the later injected portions, so that there is a substantially gradual decrease in viscosity upstream o flow in the reservoir, or toward the injection well.

Reasonable variations and modifications are possible within the scope of our invention which sets forth method and apparatus for programming and method and apparatus for liuid ooding..

We claim:

1. Means for miscible fiuid displacement of uids from an underground reservoir penetrated 'by an injection well and a production well comprising:

a first pump for injecting a first displacing fluid into said injection well; a second pump to inject a second displacing tiuid into said injection well;

a first driving motor for said first pump;

a second driving motor for said second pump;

an electrical pulse generator;

a switching relay to connect said first motor to a source of electrical energy in a first position of a contact thereof and to connect said second motor to a source of electrical energy in a second position of said contact;

a first electro-mechanical switching means to count the pulses generated by said generator and to actuate said switching relay to change the position of said contact once for a rst predetermined number of pulses from said generator; and

a second electro-mechanical switching means to count said pulses and to actuate said switching relay tochange the position of said contact once for a second predetermined number of said pulses.

2. A method for miscible displacement of a fluid from an underground reservoir penetrated by an injection well and a production well comprising the steps of:

injecting a first displacement fiuid into said injection well;

alternately injecting a second displacement iiuid;

generating a plurality of constant interval electrical pulses;

counting said pulses and actuating a switching relay once for a rst predetermined number of said pulses to change from one of said displacing fluids to thc other; and

countingsaid pulses and actuating said relay once for a second predetermined number of said pulses to change back to said one iiuid.

3. Means for miscible fluid displacement of liuids from an underground reservoir penetrated by an injection well and a production well comprising:

a first valve to control the injection of a first displacing iuid into said injection well;

a second valve to control the injection of ,a second displacing fiuid into said injection well;

first electrical actuating means for said first valve;

second electrical actuating means for said second valve;

an electrical pulse generator to transmit pulses at regular intervals;

a switching relay to connect said first actuating meansv to a source of electrical energy in a first position o a contact thereof and to connect said second electrical actuating means to a source of electrical en'ergy in a second position of said contact;

a first electro-mechanical switching means to count the pulses generated Iby said generator and to actuate 7 8 said switching relay to change the position of said once for a first predetermined number of pulses from contact once for a rst predetermined number of said generator; and said pulses; and a second electro-mechanical switching means to count a second electro-mechanical switching means to count said pulses and to actuate said relay to change the said pulses and to actuate said switching relay to 5 position of said contact once for a second predechange the position of said Contact once for a second termined number of said pulses. predetermined number of said pulses. 4. Means for miscible fluid displacement of uids from References Cited by the Examiner an underground reservoir penetrated by an injection well UNITED STATES PATENTS and a production well comprising: i0 2496 779 2/1950 De jong 317 14l first iiow control means for controlling the flow of a 2503901 M1950 chaca 367-132 X rst displacing uid into said injection well; 2867277 H1959 Wemu"t"al"" 166.9 second ow control means for controlling ow of a 2911156 11/1959 Freelaxgl B51524115 X second displacing uid into said injection well; 2927637 3/1960 Dra r 1`66 9 first electrical actuating means for said first ow conl5 2962610 11/1960 Huslgnd "'13'7 624 u ci means.; 2,994,814 8/1961 Griswoid 137-62411 second electrical actuating means for said second ow 3 O30 015 H1962 Wieslander 12,7 624 n control means; l an electrical pulse generator to transmit pulses at reguxagret al 307 l'' lar intervals; 20 a switching relay to connect said first electrical actuat- 3198967 8/1965 Roberts 301-1 41'4 ing means to a source of electrical energy in a rst OTHER REFERENCES position of a Contact thereof and to connect said Eagle Signal Company HZ Series Micmnex Reset second electrical actuating means to a source of Counter, Bulletin 720 N0vember1959 electrical energy in a second position of said con- 3 ftlact; l t h l t`h h CHARLES E. OCONNELL, Primary Examiner. a rst e ec io-rnec anica swi c ing means to count t e pulses generated by said generator and to actuate NORMAN YUDKOFF Examiner' said relay to change the position of said contact C. H. GOLD, D. H. BROWN, Assistant Examiners. 

2. A METHOD FOR MISCIBLE DISPLACEMENT OF A FLUID FROM AN UNDERGROUND RESERVOIR PENETRATED BY AN INJECTION WELL AND A PRODUCTION WELL COMPRISING THE STEPS OF: INJECTING A FIRST DISPLACEMENT FLUID INTO SAID INJECTION WELL; ALTERNATELY INJECTING A SECOND DISPLACEMENT FLUID; GENERATING A PLURALITY OF CONSTANT INTERVAL ELECTRICAL PULSES; COUNTING SAID PULSES AND ACTUATING A SWITCHING RELAY ONCE FOR A FIRST PREDETERMINED NUMBER OF SAID PULSES TO CHANGE FROM ONE OF SAID DISPLACING FLUIDS TO THE OTHER; AND COUNTING SAID PULSES AND ACTUATING SAID RELAY ONCE FOR A SECOND PREDETERMINED NUMBER OF SAID PULSES TO CHANGE BACK TO SAID ONE FLUID. 